Changes of intracellular calcium of cultured myoblast induced by cyclic stretch

Objective To elucidate the effects of stretch and acetylcholine on the intracellular calcium of myoblast and study the remodeling reaction of muscle in a variety of mechanical environments.Methods Myoblasts from maxillofacial skeletal muscle of one week old male Sprague-Dawley rats were cultured and stretched cyclicly using a four-point bend device.Fluo-3 as the Ca~(2+) indicator was used to determine the intracellular calcium concentration.Acetylcholine was added to the cultured liquid under the microscope.Results The elevation of the intracellular calcium induced by stretch was significantly higher than induced by acetylcholine and there was no additional effect on the intracellular calcium when acetycholine was applied to the stretched myoblast.Conclusion The results suggested calcium as a signal molecule was involved in the muscle remodeling process induced by stretch.